172520017 has 4 divisors (see below), whose sum is σ = 175348276. Its totient is φ = 169691760.

The previous prime is 172520009. The next prime is 172520027. The reversal of 172520017 is 710025271.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 710025271 = 31 ⋅22904041.

It can be written as a sum of positive squares in 2 ways, for example, as 85359121 + 87160896 = 9239^2 + 9336^2 .

It is a cyclic number.

It is not a de Polignac number, because 172520017 - 2³ = 172520009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 172519973 and 172520000.

It is not an unprimeable number, because it can be changed into a prime (172520027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1414038 + ... + 1414159.

It is an arithmetic number, because the mean of its divisors is an integer number (43837069).

Almost surely, 2^172520017 is an apocalyptic number.

It is an amenable number.

172520017 is a deficient number, since it is larger than the sum of its proper divisors (2828259).

172520017 is an equidigital number, since it uses as much as digits as its factorization.

172520017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2828258.

The product of its (nonzero) digits is 980, while the sum is 25.

The square root of 172520017 is about 13134.6875486248. The cubic root of 172520017 is about 556.6896719589.

Adding to 172520017 its reverse (710025271), we get a palindrome (882545288).

The spelling of 172520017 in words is "one hundred seventy-two million, five hundred twenty thousand, seventeen".